Scattered to gregarious among needles under
Juniperus communis. Occasionally solitarily on
small Juniperus twigs. Regular late autumn in Tjøme
on the west side of the Oslo fjord. Rare or possibly overlooked. See The Norwegian Mycological Database.
Pileus 6-12(-21) mm across,
cylindrical or more or less hemispherical when young, then
conical or obtusely conical to parabolical, occasionally
with a small umbo; translucent-striate, sulcate, dry, glabrous;
pale yellow to greenish yellow or olivaceous with almost
no yellow components, or olivaceous centre with paler, yellowish
margin; drying to pale yellow all over. Lamellae
12-19 reaching the stipe, ascending, narrowly adnate, occasionally
with a short decurrent tooth, becoming slightly intervenose
with age; yellowish to cream coloured or pale grey to white,
with the edge concolorous. Stipe
50-65 x 1-1.5 mm, straight to somewhat flexuous, often
curved towards the base, firm, terete, equal, glabrous except
for the pruinose apex; the apex whitish or pale grey, darker
grey to brownish below, occasionally with a yellow component;
the base densely covered with long, coarse, flexuous, whitish
fibrils. Odour not distinct. Taste
30-36 x 6.5-8 µm, clavate, with clamps or with abortive
clamps or clampless, 2-spored, with sterigmata 8-9 µm
long. Spores 8.5-11.2 x 6.2-8.2 µm,
Q 1.2-1.6, Qav ~ 1.4, smooth, broadly pip-shaped, amyloid. Cheilocystidia
15-40 x 6.5-17 µm, forming a sterile band, clavate,
clamped, or with an abortive clamp or clampless, covered
with unevenly spaced, fairly coarse, simple, cylindrical,
straight to curved excrescences 2-8(-20) x 0.9-2 µm.
Pleurocystidia absent. Lamellar
trama vinescent in Melzer's reagent. Hyphae
of the pileipellis ca 2.5 µm wide,
clamped or clampless, densely covered with simple to furcate,
cylindrical excrescences 2-4.5 x 0.9 µm, somewhat
of the cortical layer of the stipe 1.8-2.5
µm wide, clamped or not, covered with simple, cylindrical
excrescences 1.8-6.5 x 0.9-1.3 µm.
Microphotos of cheilocystidia and hyphae of the pileipellis
Mycena citrinovirens was originally
described from Greenland in 1955. It has been found regularly
in two Norwegian localities since 1988 (Aronsen
1994), and recently it seems to have been collected
in Denmark too. It belongs to Mycena sect.
Mycena, where it seems to have a somewhat aberrant
position. It can be distinguished from the other members
of the section on account of the small size, the yellowish
colours in the pileus, and the typical growth on Juniperus
needles. In the field it may be confused with Mycena
citrinomarginata Gillet, but that species can easily
be distinguished because of completely different cheilocystidia.
The Norwegian collections generally are fairly small, with a pileus less than 10 mm, but one collection from 2006 had a pileus measuring up to 21 mm across.
to key to sect. Mycena
Mycena citrinovirens paper.